Non-Adiabaticity, Chaos and Topological Effects on Nuclear Collective Dynamics

Abstract

I review the role played by level crossings for collective motion in the presence of intrinsic degrees of freedom. Level crossings induce monopole gauge potentials, which act as sources of chaos for the collective dynamics. As a result, collective dynamics can develop distinct components, including trapped, quasi-trapped and quasi-free motion. From the point of view of large amplitude shape diffusion, level crossings result in memory effects, which on certain time scales, results in fractional Brownian motion, a behavior not contained in the standard Fokker-Plank approach to shape diffusion. Rather, the appropriate class of diffusion processes for collective dynamics seems to be Levy diffusion. I outline a series of open problems related to the microscopic understanding of diffusion and dissipation.